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“发现”号的命名,源自于一艘18世纪的英国探险船——伴随著名的詹姆斯·库克船长远征南太平洋的“发现”号。在库克船长的探险中,完成了包括发现夏威夷群岛、新西兰乃至确认澳洲大陆存在等功绩,而同行中的另外一艘探险船“奋进”号也成为美国航空航天局另一架航天飞机“奋进”号的命名由来。除此之外,库克船长也曾搭乘“发现”号探索南阿拉斯加与加拿大西北之间的海岸线。虽然当时正值美国独立战争期间, 相似文献
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熟练的船长在他们的航位推算上可能非常精确,这就是为什么对这样的船长的需求量总是很大的原因.然而,即使最好的船长,也难以保证他的船不遭到风暴的袭击而在不知方向不知速度的情况下行驶.等到风平浪静的时候,那艘船可能已经在海上完全迷航了.直到17世纪中叶,人们才造出精确的时钟在船上使用,有了时钟,船只才不再迷航. 相似文献
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巴西 1958年1月初,一艘巴西的水文船"索丹纳海军上将"号出访特里尼达岛.在它出访归来正准备驶入巴西时,在船的上空中出现了一个金属圆盘,船上的50余人都看见了它.当时摄影记者阿尔米洛·巴罗纳也在人群中,他不失时机地抓拍了五张照片,并很快洗印出来.为了避免相片有假,按照水文船船长的命令,船上的两名船员监督了洗印的全部过程. 相似文献
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一艘葡萄牙籍商船“弗龙泰拉”号在大西洋的百幕大海域遇到狂风,7天来船就像一片树叶在浪峰间起浮.船员早已疲惫不堪,别说工作.就是躺在床上大脑也是一片空白。对这样的鬼天气大家想的不是听天由命.就是对船长怨声载道,因为百慕大水域本来就是谈海色变的魔鬼三角区.躲避还来不及呢,谁知这个年轻的船长却偏偏不信邪,敢在魔鬼区里航行赶船期,大家背后不仅咒骂他.有些人恨不得他突然得暴病死去或掉到海里喂鱼。 相似文献
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正开发低成本航天器、开放航天基础设施、开展航天保险业务是商业航天不可或缺的三个必要条件。当前我国的低成本航天器全面开花,航天基础设施也在逐步向商业领域倾斜,航天保险却相对发展滞后。航天和保险原本是并不相干的两个领域,但基于航天器固有的高投资、高风险属性,要想吸引社会资本开展商业化运作就必须建立起一套行之有效的风险损失管控机制。目前我国正处于航天大国向航天强国迈进的关键历 相似文献
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China's manned spaceflight missions have been introduced briefly, and the research planning of space sciences for China's Space Station (CSS) has been presented with the topics in the research areas, including:life science and biotechnology, microgravity fluid physics and combustion science, space material science, fundamental physics, space astronomy and astrophysics, earth sciences and application, space physics and space environment, experiments of new space technology. The research facilities, experiment racks, and supporting system planned in CSS have been described, including:multifunctional optical facility, research facility of quantum and optic transmission, and a dozen of research racks for space sciences in pressurized module, etc. In the next decade, significant breakthroughs in space science and utilization will hopefully be achieved, and great contributions will be made to satisfy the need of the social development and people's daily life. 相似文献
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《空间科学学报》2016,(5)
China's manned spaceflight missions have been introduced briefly,and the research planning of space sciences for China's Space Station(CSS) has been presented with the topics in the research areas,including:life science and biotechnology,microgravity fluid physics and combustion science,space material science,fundamental physics,space astronomy and astrophysics,earth sciences and application,space physics and space environment,experiments of new space technology.The research facilities,experiment racks,and supporting system planned in CSS have been described,including:multifunctional optical facility,research facility of quantum and optic transmission,and a dozen of research racks for space sciences in pressurized module,etc.In the next decade,significant breakthroughs in space science and utilization will hopefully be achieved,and great contributions will be made to satisfy the need of the social development and people's daily life. 相似文献
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任务空间内空间机械臂的自适应控制 总被引:1,自引:0,他引:1
对于本体资态受控而位置不受控的空间机械臂系统,在任务空间内给出了一种自适应控制算法;证明了当系统存在参数不确定时,该算法不但可以保证末端执行器任务空间内位置轨迹跟踪误差的渐近收敛,而且还可保证关节空间内角偏差及角偏差速率的渐近收敛;仿真结果验证了算的有效性。 相似文献
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LIU Siqing ZHONG Qiuzhen GONG Jiancun SHI Liqin CHEN Dong MIAO Juan CAI Yanxia BAI Meng MA Wenzhen LI Zhitao LIU Fanghua CHEN Yanhong 《空间科学学报》2018,38(5):781-787
Strategic Priority Research Program on Space Science has gained remarkable achievements. Space Environment Prediction Center (SEPC) affiliated with the National Space Science Center (NSSC) has been providing space weather services and helps secure space missions. Presently, SEPC is capable to offer a variety of space weather services covering many phases of space science missions including planning, design, launch, and orbital operation. The service packages consist of space weather forecasts, warnings, and effect analysis that can be utilized to avoid potential space weather hazard or reduce the damage caused by space storms, space radiation exposure for example. Extensive solar storms that occurred over Chinese Ghost Festival (CGF) in September 2017 led to a large enhancement of the solar energetic particle flux at 1 AU, which affected the near Earth radiation environment and brought great threat to orbiting satellites. Based on the space weather service by SEPC, satellite ground support groups collaborating with the space Tracking, Telemetering and Command system (TT&C) team were able to take immediate measures to react to the CGF solar storm event. 相似文献
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正目前,商业航天正在与民用航天、军事航天一起,成为航天的重要组成部分,推动世界航天进入以全面商业化、大众创新和军民融合为特征的航天新时代—航天2.0(Space2.0)时代。世界商业航天发展有什么经验教训?中国商业航天面临怎样的机遇和挑战?1世界航天进入Space2.0时代20世纪,美苏两个大国的冷战是推动航天技术最初发展的主要动力。随着冷战结束和航天技术的逐 相似文献
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